Dialkylaminosilane is a compound having a silicon atom and a nitrogen atom in a molecule. Particularly, a high-purity product having a low content of highly corrosive halogen including chlorine has been recently desired in an electronics & IT materials area, such as a semiconductor insulating film material and a super-water repellent agent on a silicon wafer surface, and a method for efficiently producing the product at a low cost has been required.
As a method for producing dialkylaminosilane, a method for synthesizing dialkylaminosilane from a reaction of dialkylamine with chlorosilane is known (Non-patent literature No. 1). However, a large amount of dialkylamine hydrochloride is produced as a by-product, in addition to objective dialkylaminosilane, and therefore in order to obtain dialkylaminosilane, reduction of volumetric efficiency caused by a large amount of a solvent has been required to be prevented, or solid-liquid separation operation such as filtration or decantation has been required.
Patent literature No. 1 discloses a method for separating dialkylamine hydrochloride produced in a large amount as a by-product, without performing solid-liquid separation such as filtration, by adding an alkaline aqueous solution thereto to dissolve dialkylamine hydrochloride in the alkaline aqueous solution, and extracting the resultant hydrochloride into an aqueous layer.
Patent literature No. 2 discloses a method for allowing dialkylamine hydrochloride produced in a large amount as a by-product to react with metal (such as magnesium), while temperature is controlled, into dialkylamine, metal chloride (such as magnesium chloride) and hydrogen to regenerate dialkylamine and to reduce an amount of salt.
Patent literature Nos. 3 and 4 disclose a method for directly producing dialkylaminosilane from metallic silicon and dialkylamine in the presence of a copper catalyst, in which no chlorosilane is used, and therefore no dialkylamine hydrochloride is formed and a halogen content is small.